Can't Lift A Denali?

flyin6 · September 25, 2008

I am finding out some very disturbing news. After talking to Rough Country and BDS, I am being told I can't lift the AWD Denali!!!!!!!!!!!!!!!

Yea, imagine my surprise, (and disappointment)! I'm being told that the truck will vibrate if I lift it all. Somehow this just doesn't sound right.

They say it is because the AWD puts constant pressure on the front driveshaft whereas a normal 2WD-4WD truck does not power the front shaft except under 4WD conditions. Well, using that logic, wouldn't a lifted 4WD truck vibrate also when using 4WD???

This makes my head hurt!

Further, one tech guy said my front drive shaft turns all the time when driving, OK, I can buy that. But then he said a 2WD-4WD truck does not turn the front driveshaft at all when cruising in 2WD! This is the part I can't quite grasp. If the axle is solidly connected to the wheel, which it is, and it is also connected to the diff, then the diff has to spin also, correct?

Well if the diff is spinning, then the axle also has to turn since it is all connected. SO the front shaft should turn, right?

And even further, my H2 Hummer is AWD, yet guys lift those things all the time. Fabtech even builds a CV front shaft to go along with their H2 lift kit. I know in that app the front shaft also spins all the time.

So who's right and who do I believe???

Zembonez · September 25, 2008

Some of the AWD hardware on the Denali is different than a standard 4x4. The kit would very likely require some unique engineering. Since there are probably 4 guys in the country wanting to lift a Denali and thousands that want to lift a typical 4x4, where would you spend your development dollars creating a kit?

On a standard 4x4, the front shaft "freewheels" when not engaged. I am not sure why that would create a vibration on the Denali.

2000DV4.8 · September 25, 2008

There was a member here that lifted his Denali...

Not sure if it was AWD, but I think it was. I'll try to find the thread.

2000DV4.8 · September 25, 2008

OK that took way too long, but I found it.

http://www.gm-trucks.com/forums/index.php?...c=78720&hl=

And it is an AWD.

mhenshaw · September 25, 2008

I am finding out some very disturbing news. After talking to Rough Country and BDS, I am being told I can't lift the AWD Denali!!!!!!!!!!!!!!!

Yea, imagine my surprise, (and disappointment)! I'm being told that the truck will vibrate if I lift it all. Somehow this just doesn't sound right.

They say it is because the AWD puts constant pressure on the front driveshaft whereas a normal 2WD-4WD truck does not power the front shaft except under 4WD conditions. Well, using that logic, wouldn't a lifted 4WD truck vibrate also when using 4WD???

This makes my head hurt!

Further, one tech guy said my front drive shaft turns all the time when driving, OK, I can buy that. But then he said a 2WD-4WD truck does not turn the front driveshaft at all when cruising in 2WD! This is the part I can't quite grasp. If the axle is solidly connected to the wheel, which it is, and it is also connected to the diff, then the diff has to spin also, correct?

Well if the diff is spinning, then the axle also has to turn since it is all connected. SO the front shaft should turn, right?

And even further, my H2 Hummer is AWD, yet guys lift those things all the time. Fabtech even builds a CV front shaft to go along with their H2 lift kit. I know in that app the front shaft also spins all the time.

So who's right and who do I believe???

On 4wheel drive trucks the driveshaft does not spin because the hubs in the front disengage.

2000DV4.8 · September 25, 2008

On 4wheel drive trucks the driveshaft does not spin because the hubs in the front disengage.

The hubs don't disengage, the front diff. does. The CV axles are spinning with the front wheels.

flyin6 · September 25, 2008

On 4wheel drive trucks the driveshaft does not spin because the hubs in the front disengage.

No hubs!

THe GMT 900 and the earlier platform have no hubs. The axle shaft is splined directly into the wheel hub. That's what that big nut is you see, it is the outside of the axle...

flyin6 · September 25, 2008

OK that took way too long, but I found it.

http://www.gm-trucks.com/forums/index.php?...c=78720&hl=

And it is an AWD.

Thanks for digging that up. I have been searching far and wide for info like this.

So now I know some brave soul has actually done it, which is encouraging...

However:

I called BDS today. They told me their kit could not be used on the Denali! (Getting confused again!) The problem is that all Denalis have stabilitrack. To disconnect the shock causes the computer to go wacko. They said you would have to use some sort of strut extension like as with the Fabtech kit. They specifically said their kit (BDS) does not use the factory shock, so how is this 2008 Denali in the link lifted with a BDS kit???????????

They also said a double cardan driveshaft would have to be fabbed, and even then, there would be some vibration. So, again, I'm looking at a picture of a raised Denali, so who's right? Who's telling the truth???

I am probably going to tackle this myself anyway. But I would at least like to start off on the right foot with the (mostly) correct parts. I can see, I will probably end up putting a standard transfer case in the truck and ditch the AWD boat anchor... We'll see...

Majorleaguebass · September 25, 2008

i bet the guy probably pulled the fuse for the stabil-track would be my guess. Good luck on swapping out systems, i think you're in for more trouble than it is worth

VMax2007 · September 25, 2008

On 4wheel drive trucks the driveshaft does not spin because the hubs in the front disengage.

The hubs don't disengage, the front diff. does. The CV axles are spinning with the front wheels.

Ding, ding, ding....we have a winner folks!!!

In 2wd, the front CV axles spin freely. There is an electric actuator in the front diff that engages/disengages the front drive shaft.

2000DV4.8 · September 25, 2008

Thanks for digging that up. I have been searching far and wide for info like this.
So now I know some brave soul has actually done it, which is encouraging...

However:

I called BDS today. They told me their kit could not be used on the Denali! (Getting confused again!) The problem is that all Denalis have stabilitrack. To disconnect the shock causes the computer to go wacko. They said you would have to use some sort of strut extension like as with the Fabtech kit. They specifically said their kit (BDS) does not use the factory shock, so how is this 2008 Denali in the link lifted with a BDS kit???????????

They also said a double cardan driveshaft would have to be fabbed, and even then, there would be some vibration. So, again, I'm looking at a picture of a raised Denali, so who's right? Who's telling the truth???

I am probably going to tackle this myself anyway. But I would at least like to start off on the right foot with the (mostly) correct parts. I can see, I will probably end up putting a standard transfer case in the truck and ditch the AWD boat anchor... We'll see...

I'd send him a PM, that'd be the best way to answer your questions.

And Jeff, what do I win?

VMax2007 · September 25, 2008

And Jeff, what do I win?

Free Line-X'ed rocker panels.

blackout07 · September 25, 2008

OK that took way too long, but I found it.

http://www.gm-trucks.com/forums/index.php?...c=78720&hl=

And it is an AWD.

Thanks for digging that up. I have been searching far and wide for info like this.

So now I know some brave soul has actually done it, which is encouraging...

However:

I called BDS today. They told me their kit could not be used on the Denali! (Getting confused again!) The problem is that all Denalis have stabilitrack. To disconnect the shock causes the computer to go wacko. They said you would have to use some sort of strut extension like as with the Fabtech kit. They specifically said their kit (BDS) does not use the factory shock, so how is this 2008 Denali in the link lifted with a BDS kit???????????

They also said a double cardan driveshaft would have to be fabbed, and even then, there would be some vibration. So, again, I'm looking at a picture of a raised Denali, so who's right? Who's telling the truth???

I am probably going to tackle this myself anyway. But I would at least like to start off on the right foot with the (mostly) correct parts. I can see, I will probably end up putting a standard transfer case in the truck and ditch the AWD boat anchor... We'll see...

Surely they meant "Autoride" and not stabilitrak. My truck has the stabilitrak feature and its functioning fine with the BDS. Removing the factory strut equipped with Autoride is the problem, as some kits are specifically designed for this.

flyin6 · September 26, 2008

i bet the guy probably pulled the fuse for the stabil-track would be my guess. Good luck on swapping out systems, i think you're in for more trouble than it is worth

You may be correct, but, nothing ventured, nothing gained. Worse case is I have a "zero time" almost new lift kit for sale for half price :-))

BTW, that truck of yours looks great. I like the look of the previous series much more that the new GMT 900 series. Way too much air dam lookin' front bumper on the newbie. But I already have a 04 burb (which will just not wear out!), and the new truck offered a new frame and that sweet 6.2L and six-speed.

Regarding the lift of the AWD. In addition to the lift kit, I believe I'm looking at a new drive shaft at a minimum. Possibly a reprogramming of the computer, or like yo said, disabling the stabilitrack (which I don't need anyway) and at worse, installing a real transfer case like everyone else in the known universe has!

flyin6 · September 26, 2008

Surely they meant "Autoride" and not stabilitrak. My truck has the stabilitrak feature and its functioning fine with the BDS. Removing the factory strut equipped with Autoride is the problem, as some kits are specifically designed for this.

There you are, sent you an email about your truck.

OK, first, you're correct, I meant autoride, not stabilitrack. Did your truck have autoride?

If so, did you remove it and just install the BDS strut?

Next, on the vibration issue, did you just bolt in the factory driveshaft, or have to do a double cardan custom driveshaft?

Finally, if you did remove the autoride shocks, how did you get around that? Computer still functioning normally?

Thanks in advance for any input!